Having twins linked to natural health and longevity
Why do women who bear twins live longer?
It's not that having twins does anything special to lengthen telomeres or change genes - it's just that women who have babies in pairs tend to be healthier and have a greater chance of bearing twins in the first place.
Contrary to the notion that childbearing is a burden for mothers who birth two at a time, the opposite seems to be true, according to the authors of a new study.
Scientists from University of Utah found women who have twins tend to remain fertile longer and often have babies later in life. They are simply healthier and it’s notable by the time they reach age 50.
Mothers who have twins are innately healthy
Demographer, Ken. R. Smith, senior author of the study and a professor of family and consumer studies said, "That innate healthiness is contributing to their ability to have twins, and it is also contributing to their longevity."
He says even though choices are made to stay healthy, women who have twins naturally seem to possess some ancestral health legacy that is shared in families.
Smith says it’s true twins can run in families, but environmental factors also play a role. He says, "It's complicated. There are so many factors that contribute to longevity, health and aging."
For the study, the researchers examined a database 6.4 million people from the early 1800s to present who were primarily Mormon immigrants. Among those, 4,603 were the mothers of twins.
Compared to women who had one baby, those who had twins had a statistically significant lower annual chance of dying after menopause – 7.6 percent for women born before 1870 and 3.3 percent for women born between 1870 and 1899.
Mothers of twins were older when they had their last child, remained fertile longer and had their babies closer together. They also lived longer after menopause.
Smith says, “There's a certain aspect of how long you're going to live and how healthy you're going to be that is innate – basically affected by your biological makeup.”
The study shows women who have twins seem to be naturally robust and healthy, making it easier to have a pair at a time. The investigation shows twinning mothers can be expected to live longer than their single child bearing counterparts.
Proceeding of the Royal Society B
"Twinning in humans: maternal heterogeneity in reproduction and survival"
Shannen L. Robson, Ken R. Smith